+ mm-damon-core-initialize-damo_filter-list-from-damos_new_filter.patch added to mm-hotfixes-unstable branch

+ mm-damon-core-initialize-damo_filter-list-from-damos_new_filter.patch added to mm-hotfixes-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm/damon/core: initialize damo_filter->list from damos_new_filter()
has been added to the -mm mm-hotfixes-unstable branch.  Its filename is
     mm-damon-core-initialize-damo_filter-list-from-damos_new_filter.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-damon-core-initialize-damo_filter-list-from-damos_new_filter.patch

This patch will later appear in the mm-hotfixes-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: SeongJae Park <sj@kernel.org>
Subject: mm/damon/core: initialize damo_filter->list from damos_new_filter()
Date: Sat, 29 Jul 2023 20:37:32 +0000

damos_new_filter() is not initializing the list field of newly allocated
filter object.  However, DAMON sysfs interface and DAMON_RECLAIM are not
initializing it after calling damos_new_filter().  As a result, accessing
uninitialized memory is possible.  Actually, adding multiple DAMOS filters
via DAMON sysfs interface caused NULL pointer dereferencing.  Initialize
the field just after the allocation from damos_new_filter().

Link: https://lkml.kernel.org/r/20230729203733.38949-2-sj@kernel.org
Fixes: 98def236f63c ("mm/damon/core: implement damos filter")
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/damon/core.c |    1 +
 1 file changed, 1 insertion(+)

--- a/mm/damon/core.c~mm-damon-core-initialize-damo_filter-list-from-damos_new_filter
+++ a/mm/damon/core.c
@@ -273,6 +273,7 @@ struct damos_filter *damos_new_filter(en
 		return NULL;
 	filter->type = type;
 	filter->matching = matching;
+	INIT_LIST_HEAD(&filter->list);
 	return filter;
 }
 
_

Patches currently in -mm which might be from sj@kernel.org are

mm-damon-core-initialize-damo_filter-list-from-damos_new_filter.patch
mm-damon-core-test-add-a-test-for-damos_new_filter.patch